1. Field of the Invention
The present invention relates to a process for the preparation of D-gluconic-.delta.-lactam with the formula: C.sub.6 H.sub.11 O.sub.5 N, ##SPC1##
from the antibiotic substance, nojirimycin. Nojirimycin, which is used as a starting material in the process of the present invention, is an antibiotic which is obtained from the culture broth of a certain species of Streptomyces (T. Niida, et al, J. Antibiotics, Ser. A 20, 62, 1967). The chemical structure of Nojirimycin has been determined as 5-amino-5-deoxy-D-glucopyranose (S. Inouye, et al, Tetrahedron, 24, 2125, 1968). D-Gluconic-.delta.-lactam not only serves as a powerful competitive inhibitor for .beta.-glucosidase (Agricultural and Biological Chemistry, Vol. 34, page 966, 1970) but also is an intermediate which is useful for the synthesis of various kinds of biologically and physiologically active substances (Japanese Pat. Application Nos. 78387/1973 and 76577/1973).
2. Description of the Prior Art
Procedures are known for the chemical oxidation of nojirimycin into D-gluconic-.delta.-lactam. For example, nojirimycin has been oxidized with hypoiodic acid (Tetrahedron, 24, page 2125, 1968) and hypobromic acid. However, when these methods are applied on an industrial scale to the preparation of D-gluconic-.delta.-lactam, the process inherently requires the handling of large amounts of iodine or bromine which are harmful to the human body. The use of such large amounts of halogen materials has the disadvantage of presenting environmental pollution problems.
A need, therefore, continues to exist for a method of oxidizing nojirimycin which does not present pollution problems and which avoids the necessity of using large amounts of halogen materials.